Figure 4. Influence of heme from meal on the α-glucosidase expression (A) and activity (B) in the R. prolixus midgut.

P – control insects fed on plasma; P + H – insects fed on hemin-enriched plasma (500 μM). Insects were fed on rabbit plasma with and without hemin. Four days after feeding, midguts (n = 20) were dissected in cold 100 mM NaCl. The α-glucosidase activity was determined by measuring the release of ρ-nitrophenolate from ρ-nitrophenyl α-D-glucopyranoside. Results shown are representative of three independent experiments run in triplicate. Plasma plus hemin is significantly different from plasma *(P<0.05).